Photo © Tony Campbell | Dreamstime.com
Nocturnal flying squirrels glide from tree to tree in East Texas forests.
By Jonah Evans
If you spend any time in the forests of East Texas at night, you may be fortunate enough to hear the high-pitched chirp of one of Texas’ most unusual and mysterious rodents — the southern flying squirrel. This tiny squirrel weighs about as much as a tennis ball and emerges after dark to begin its nightly activities; flying squirrels are the only nocturnal squirrels in North America.
Despite what their name suggests, they don’t actually fly. Their name comes from their ability to glide from tree to tree with the help of specially adapted flaps of skin that stretch from wrist to ankle along each side of their body. They have been observed gliding distances as far as 100 yards. They are very nimble in the air, and with the help of their large, flat tail, flying squirrels can quickly shift directions while gliding. And they can do all this in complete darkness in the middle of the night.
Flying squirrels are a drab, brownish color much like other squirrels, at least under normal lighting conditions. Researchers recently discovered that under an ultraviolet light, this curious creature glows brilliant pink, one of the few mammals known to fluoresce (opossums are another). The reason for this feature is still unknown.
Flying squirrels’ ability to race along tree branches in the dark is aided by their very large ebony eyes. Some researchers have suggested that they may use their high-pitched, sometimes ultrasonic, chirps as a form of echolocation to aid in navigation during dark nights, though this is largely an untested hypothesis at this time.
In Texas, flying squirrels are found primarily in mature forests east of Interstate 35 — they prefer tall trees as launch pads to glide around the forest. Because of their secretive and nocturnal habits, very little is known about their abundance and distribution. Thanks to iNaturalist.org, a citizen science website for reporting animal and plant observations, we know they have recently been spotted around Bastrop, Houston and Dallas.
Flying squirrels nest primarily in tree cavities but will sometimes construct a nest out of leaves or moss; it’s also fairly common to find them roosting in bird houses.
In the winter, they are known to aggregate in communal nests. It’s thought that they might do this in order to stay warm. While the groups usually have fewer than 10 individuals, some have been reported to contain as many as 50.
The southern flying squirrel is a unique and fascinating creature, but it can easily go undetected. If you live in their habitat, take a walk in the evening and listen for their telltale chirps. You may just have the chance to get to know a new neighbor.